Heart and vascular disease are major problems in the United States and throughout the world. Conditions such as atherosclerosis result in blood vessels becoming blocked or narrowed. This blockage can result in lack of oxygenation of the heart, which has significant consequences because the heart muscle must be well oxygenated in order to maintain its blood pumping action.
Occluded, stenotic, or narrowed blood vessels may be treated with a number of relatively non-invasive medical procedures including percutaneous transluminal angioplasty (PTA), percutaneous transluminal coronary angioplasty (PTCA), and atherectomy. Angioplasty techniques typically involve the use of a balloon catheter. The balloon catheter is advanced over a guidewire such that the balloon is positioned adjacent a stenotic lesion. The balloon is then inflated and the restriction of the vessel is opened. During an atherectomy procedure, the stenotic lesion may be mechanically cut away from the blood vessel wall using an atherectomy catheter.
The non-invasive medical procedures identified above typically gain access to the vasculature through an opening formed in the femoral artery. For obvious reasons, once the procedure is completed the opening in the femoral artery will need to be closed. This may include applying direct pressure at the wound site. Alternatively, a device may be used to assist in the closing of the artery.
A wide variety of medical devices have been developed for medical uses, for example, in non-invasive medical procedures. Some of these devices include devices for closing an opening in a body lumen such as the femoral artery. Closure devices for closing an opening in a body lumen may include a plug such as a collagen sponge, a dissolving anchor, and a suture coupling the plug to the anchor. The dissolving anchor may be configured to dissolve in the body lumen within about 60 to 90 days or less. At least a portion of the dissolving anchor may be disposed within the body lumen. Although the anchor may have served the purpose of positioning and securing the plug adjacent to the vessel within the first few hours following surgery, such anchors are frequently designed to dissolve more slowly to ensure that they continue to function during the post operative period and to minimize the likelihood that a significant piece of the anchor may be released into the blood stream during the dissolution process. Other difficulties may arise if it becomes necessary to re-enter the wound site before the anchor has fully dissolved.
Accordingly, it would be desirable to provide an anchor which dissolves rapidly and controllably while positioned within the vessel.